Unlike restaurants that use frozen fries, Five Guys goes through the time-consuming effort of machine-cutting skin-on fries, which are then blanched, or deep-fried, to boil the spuds and provide a soft, tasty interior. The fries are finished later by frying them at a higher temperature to provide a crispy crust.

Murrell says many frozen fries are “dehydrogenated” and sop up oil when they are cooked. Water in fresh potatoes, however, will boil when they are cooked, and little oil is lost, which is important at Five Guys because it uses more expensive peanut oil.

The chain also features Cajun-style fries, dusted with McCormick Cajun Seasoning.

While diners may be split over whether they go to Five Guys for the burgers or the fries, there’s no question that most customers of Boise Fry Co. are there primarily for the potatoes. The Boise, Idaho, restaurant’s motto is “burgers on the side.”

Boise Fry offers numerous potato varieties that change seasonally. In the fall, for instance, there are Russets, Yukon Golds, and Purple Peruvians from Idaho; sweet and white potatoes from California; and German Butterballs.

Fries are sold in four shapes and cost $2.39 for a small serving and $4.79 for a bowl. A wide array of seasonings, such as rosemary garlic salt and vanilla, are available, as are eight dipping sauces, led by blueberry ketchup and sonti sauce.

“Dips and seasonings provide so many taste options for customers at relatively little additional cost,” Lingle says. However, Boise Fry’s special fries, which are flash fried in duck fat and seasoned with black truffle salt, carry a hefty $8 price tag.

A number of other quick-service and fast-casual restaurants dotted across the country are devoted to selling upscale fries as well.

At Fritz, the Place to Eat, in Keene, New Hampshire, owner Jessica Graveline brought ideas garnered during her years in New York City, where she frequented Pomme Frites, which is known for its fresh-cut, twice-cooked Belgian frites and dipping sauces.

“I was looking for a high-margin product out there, and this is probably the highest margin going,” says Graveline, who grew up on a potato farm. She began with fries and paninis and has since expanded into salads and burgers.

No U.S. restaurant has expanded a fries-based menu into numerous units, but that isn’t the case in Canada, where New York Fries has grown to nearly 200 stores, mainly in mall food courts. The fries are also served at growing sister chain, South St. Burger Co.

Potatoes are kept in temperature-controlled facilities and are hand-cut at every store, where the slices are stored in cold water before going into a three-step cooking process, says marketing manager Alyssa Berenstein.

The taters are fried in sunflower oil, and no timers are involved “because the potato chemistry changes from season to season.” Instead, cooks rely on their training and experience to tell when each stage of the process is done.

Customers can get cheese sauce, gravy, or sour cream for dipping, and there are several seasonings and vinegars available.

New York Fries also sells a Canadian favorite: poutine. The dish is a base of fries, topped with cheese curd (similar to fresh mozzarella) and gravy, which melts the cheese and provides a savory flavor.

“You don’t see poutine much in the States, but it could become a regional item,” says Idaho expert Odiorne.

One type of potato getting increased interest for fries among American restaurant operators is the sweet potato. The growing demand for these orange tubers is in large part because they are seen as healthier, packed with vitamins, nutrients, and fiber.

“Sweet potatoes are off the chart,” says Bonnie Urresti, director of customer marketing for ConAgra’s Lamb Weston division, an industry provider of frozen potato products. “Hardly a customer we talk to doesn’t make that a topic of the conversation.”

The company invested $120 million in a state-of-the-art sweet potato processing plant in Delhi, Louisiana, that opened this fall. Louisiana is the third-largest sweet potato producing state behind North Carolina and Mississippi.

As with many of the fries of all shapes and sizes sold by Lamb Weston, sweet potato fries are partially cooked before being frozen and shipped to restaurants. “There is no difference in [handling] sweet potato fries from an operator’s perspective,” Urresti says.